The present invention relates to a foldable mobile telephone which is constituted of a main body and an open/close-able lid and in particular is capable of detecting the open/close state of the lid.
As a conventional foldable mobile telephone, the Japanese Patent Laid-Open Publication No. HEI 7-15493 discloses the foldable mobile telephone which is constituted of a main body provided a magnet, a lid had a lead switch and a detecting circuit detecting the on/off state of the lead switch.
However, in the conventional foldable mobile telephone, the relationship the position of the magnet and the lead switch is important, therefore the mounting condition at the manufacturing process to be satisfied with this relation of the position is a burden. Moreover, the conventional foldable mobile telephone has a problem that the lead switch acts erroneously influenced by the outside magnetic field. Furthermore, the conventional foldable mobile telephone has a problem that the magnetic field of the magnet may influence magnetic recording devices such as a magnetic card.
It is therefore an object of the present invention to provide a foldable mobile telephone whose mounting condition during the manufacturing process is not critical and is not erroneously influenced by the outside magnetic field and does not influence badly the magnetic recording devices such as a magnetic card.
According to a first aspect of the present invention, to solve the above mentioned problems, at a foldable mobile telephone which is constituted of a main body and a lid being open/close-able for said main body, the present invention provides a receiver for ultrasonic wave provided in said main body, a microphone for ultrasonic wave provided in said lid, an ultrasonic oscillator for giving an ultrasonic signal to said receiver for ultrasonic wave and an open/close state judging means for judging the open/close state of the lid by judging whether the level of an ultrasonic detecting signal is higher or lower than a decided level receiving the ultrasonic detecting signal from said microphone for ultrasonic wave.
According to a second aspect of the present invention, at a foldable mobile telephone which is constituted of a main body and a lid being open/close-able for said main body, the present invention provides a microphone for ultrasonic wave provided in said main body, a receiver for ultrasonic wave provided in said lid, an ultrasonic oscillator for giving an ultrasonic signal to said receiver for ultrasonic wave, and an open/close state judging means for judging the open/close state of the lid by judging whether the level of an ultrasonic detecting signal is higher or lower than a decided level receiving the ultrasonic detecting signal from said microphone for ultrasonic wave.
According to a third aspect of the present invention, at a foldable mobile telephone which is constituted of a main body and a lid being open/close-able for said main body, the present invention provides a microphone for ultrasonic wave provided in said main body, a receiver for ultrasonic wave provided in said lid, an ultrasonic oscillator for intermittently giving an ultrasonic signal at each fixed interval to said receiver for ultrasonic wave, an open/close state judging signal generating means for generating the open/close state judging signal judged the open/close state of the lid by judging whether the level of an ultrasonic detecting signal is higher or lower than a decided level receiving the ultrasonic detecting signal from said microphone for ultrasonic wave, and a judged result memory means for memorizing the judged result of said open/close state judging signal from said open/close state judging signal generating means.
According to a fourth aspect of the present invention, at a foldable mobile telephone which is constituted of a main body and a lid being open/close-able for said main body, the present invention provides a receiver for ultrasonic wave provided in said main body, a microphone for ultrasonic wave provided in said lid, an ultrasonic oscillator for intermittently giving an ultrasonic signal at each fixed time to said receiver for ultrasonic wave, an open/close state judging signal generating means for generating the open/close state judging signal judged the open/close state of the lid by judging whether the level of an ultrasonic detecting signal is higher or lower than a decided level receiving the ultrasonic detecting signal from said microphone for ultrasonic wave, and a judged result memory means for memorizing the judged result of said open/close state judging signal from said open/close state judging signal generating means.